# Copyright (c) 2016, Hiroaki Nakamura <hnakamur@gmail.com>
# Simplified BSD License (see LICENSES/BSD-2-Clause.txt or https://opensource.org/licenses/BSD-2-Clause)
# SPDX-License-Identifier: BSD-2-Clause

from __future__ import annotations


import http.client as http_client
import json
import os
import socket
import ssl
import typing as t
from urllib.parse import urlparse

from ansible.module_utils.urls import generic_urlparse

# httplib/http.client connection using unix domain socket
HTTPConnection = http_client.HTTPConnection
HTTPSConnection = http_client.HTTPSConnection


class UnixHTTPConnection(HTTPConnection):
    def __init__(self, path: str) -> None:
        HTTPConnection.__init__(self, "localhost")
        self.path = path

    def connect(self):
        sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
        sock.connect(self.path)
        self.sock = sock


class LXDClientException(Exception):
    def __init__(self, msg: str, **kwargs) -> None:
        self.msg = msg
        self.kwargs = kwargs


class LXDClient:
    def __init__(
        self,
        url: str,
        key_file: str | None = None,
        cert_file: str | None = None,
        debug: bool = False,
        server_cert_file: str | None = None,
        server_check_hostname: bool = True,
    ) -> None:
        """LXD Client.

        :param url: The URL of the LXD server. (e.g. unix:/var/lib/lxd/unix.socket or https://127.0.0.1)
        :param key_file: The path of the client certificate key file.
        :param cert_file: The path of the client certificate file.
        :param debug: The debug flag. The request and response are stored in logs when debug is true.
        :param server_cert_file: The path of the server certificate file.
        :param server_check_hostname: Whether to check the server's hostname as part of TLS verification.
        """
        self.url = url
        self.debug = debug
        self.logs: list[dict[str, t.Any]] = []
        self.connection: UnixHTTPConnection | HTTPSConnection
        if url.startswith("https:"):
            self.cert_file = cert_file
            self.key_file = key_file
            parts = generic_urlparse(urlparse(self.url))
            ctx = ssl.create_default_context(ssl.Purpose.SERVER_AUTH)
            if server_cert_file:
                # Check that the received cert is signed by the provided server_cert_file
                ctx.load_verify_locations(cafile=server_cert_file)
            ctx.check_hostname = server_check_hostname
            ctx.load_cert_chain(cert_file, keyfile=key_file)  # type: ignore # TODO!
            self.connection = HTTPSConnection(parts.get("netloc"), context=ctx)
        elif url.startswith("unix:"):
            unix_socket_path = url[len("unix:") :]
            self.connection = UnixHTTPConnection(unix_socket_path)
        else:
            raise LXDClientException("URL scheme must be unix: or https:")

    def do(self, method: str, url: str, body_json=None, ok_error_codes=None, timeout=None, wait_for_container=None):
        resp_json = self._send_request(method, url, body_json=body_json, ok_error_codes=ok_error_codes, timeout=timeout)
        if resp_json["type"] == "async":
            url = f"{resp_json['operation']}/wait"
            resp_json = self._send_request("GET", url)
            if wait_for_container:
                while resp_json["metadata"]["status"] == "Running":
                    resp_json = self._send_request("GET", url)
            if resp_json["metadata"]["status"] != "Success":
                self._raise_err_from_json(resp_json)
        return resp_json

    def authenticate(self, trust_password):
        body_json = {"type": "client", "password": trust_password}
        return self._send_request("POST", "/1.0/certificates", body_json=body_json)

    def _send_request(self, method: str, url: str, body_json=None, ok_error_codes=None, timeout=None):
        try:
            body = json.dumps(body_json)
            self.connection.request(method, url, body=body)
            resp = self.connection.getresponse()
            resp_data = resp.read()
            resp_json = json.loads(resp_data)
            self.logs.append(
                {
                    "type": "sent request",
                    "request": {"method": method, "url": url, "json": body_json, "timeout": timeout},
                    "response": {"json": resp_json},
                }
            )
            resp_type = resp_json.get("type", None)
            if resp_type == "error":
                if ok_error_codes is not None and resp_json["error_code"] in ok_error_codes:
                    return resp_json
                if resp_json["error"] == "Certificate already in trust store":
                    return resp_json
                self._raise_err_from_json(resp_json)
            return resp_json
        except socket.error as e:
            raise LXDClientException("cannot connect to the LXD server", err=e) from e

    def _raise_err_from_json(self, resp_json):
        err_params = {}
        if self.debug:
            err_params["logs"] = self.logs
        raise LXDClientException(self._get_err_from_resp_json(resp_json), **err_params)

    @staticmethod
    def _get_err_from_resp_json(resp_json):
        err = None
        metadata = resp_json.get("metadata", None)
        if metadata is not None:
            err = metadata.get("err", None)
        if err is None:
            err = resp_json.get("error", None)
        return err


def default_key_file() -> str:
    return os.path.expanduser("~/.config/lxc/client.key")


def default_cert_file() -> str:
    return os.path.expanduser("~/.config/lxc/client.crt")
